electric boat motors

[HoffaLives]

a customer has contracted me to setup the electrics on his boat; he's also pulling the perkins and putting in a Thoosa 1700, 96 volt electric motor & 8 8D AGMs. I've done some basic research and the engineering looks pretty sweet, but i'm wondering if anyone has any experience with these? the install looks pretty straightforward, but i'm wondering how it will all work out for the guy as i've never seen one of these set up and running.

[Freesail99]

If you need to just motor in and out of your slip, the electric motor works great. If you need to motor for hours at a time they don't.

[sailboy21]

One of my fellow "Rawsoneers" fitted his Rawson 30 with a golf cart motor connected to his original prop. Not high tech at all, but he claims to be able to motor out and go sailing etc.. no problem. But, as already said, don't try to go anywhere. Personally, I am quite interested in the "Torquedo." Wonder if they are considering a sail drive version?

[Hartley18]

The other thing to think about is the weight.

Usually an electric motor plus batteries weighs quite a bit more than a small auxilliary.

[Idiens]

All you need is an adequate supply of sunshine ....

http://www.solarnavigator.net/transatlantic_21.htm

[sailboy21]

Originally Posted by Hartley18

The other thing to think about is the weight.

Usually an electric motor plus batteries weighs quite a bit more than a small auxilliary.

Very true. In the boat I mentioned, the owner removed ballast from the keel to made room for the batteries. However, he still had batteries everywhere. I think the real trick will be that Li-ion battery technology becomes affordable.
When I googled "Thoosa 1700" I got a bunch of results for mythical creatures. If that the right spelling? People and companies have been building electric cars and boats for at least a hundred years now, if you assume we have a free market this goes to show which system is more practical.

I always like discussing this subject, because I know, someday, somewhere, someone will come up with the silver bullet, and the world will change. But for now, here is a comparison to some commonly available battery types: Prices are a shotgun average from nextag.com. Weight from a spring scale, and approximate.




Of course prices vary.. and these are what I had around the house. Li-Ion equivalent for the Lead Acid seems to anywhere from $50 to $200.

[fcsob]

OSSA Powerlite makes a complete conversion for repowering your boat. they range from 20hp to 800hp.Read more @www.ossapowerlite.com/.In septembers Latitudes & Attitudes two boats are featured with electric motors.

[Idiens]

Also

http://www.fischerpanda.de/products/eng/154

have a partner company for diesel electric combinations.

It works out almost exactly twice the price of a diesel propulsion system of the same power.

[ChicagoNewport27]

Originally Posted by sailboy21

...When I googled "Thoosa 1700" I got a bunch of results for mythical creatures. If that the right spelling?

The Thoosa is manufactured by ASMO Marine
http://www.asmomarine.com/2005/asmo_uk/01.shtml

[ChicagoNewport27]

I've been researching this too.

I've been waffling between getting a diesel engine (in the hope of eventually switching over to biodiesel), or to go with an electric inboard, such as the Thoosa 7000 (suitable for my 27' ft sloop).

Since I only am a daysailer/weekender, and usually only cruise less than 50 miles from port, I would feel comfortable with the range afforded by the inboard electric, especially seeing as those nifty Thoosa's can regenerate the batteries when the engine is off by using the slowly turning prop as a dynamo for power generation (this power generation can even work using a feathering prop, but obviously less effectively). Coupled with a solar panel or two, maybe a wind genset, my batteries could basically maintain themselves during the week when I'm not using the boat, which would eliminate the need for a shorepower connection to top up the batteries (my boat is on a mooring, so shorepower is out).

Like I said, I'm basically a weekender, so I dont need to motor for hundreds of miles. I motor in and out of the harbor, or over to the pump-out dock, thats it. If I'm trying to evade a storm, sometimes I'll fire up the motor, however, and that might take more juice than the batteries could provide. If I needed more range with the Thoosa, I could install a diesel generator to top up the batteries, or, if I'm feeling like a cheapskate, I could just use my Honda 2000i gas genny to give me enough juice to maintain the batteries for longer trips under power.

Anyway, since the Thoosa package sells for just over $7k, I'll have plenty of time to debate between biodiesel and electric as I save my pennies for the next few years.

Hopefully, by the time I've made my decision, the cost of batteries and electric marine inboards willhave come down a bit.